fungal ecology 3 (2010) 9–19 available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/funeco Diversity and fruiting pattern of macrofungi associated with chestnut (Castanea sativa) in the Tra´s-os-Montes region (Northeast Portugal) Paula BAPTISTAa,*, Anabela MARTINSa, Rui Manuel TAVARESb, Teresa LINO-NETOb aCIMO/Escola Superior Agra´ria do Instituto Polite´cnico de Braganc¸a, Quinta de Sta Apolo´nia, Campus de Santa Apolonia, Apartado 1172, 5301-855 Braganc¸a, Portugal bCenter for Biodiversity, Functional & Integrative Genomics (BioFIG), Departamento de Biologia, Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal article info abstract Article history: The chestnut (Castanea sativa) agro-ecosystem is of great social, economic and landscape Received 24 January 2009 importance in NE Portugal. There are multiple resources associated with this crop, among Revision received 17 May 2009 them fruit and wood production and mushroom harvesting. However, information about Accepted 15 June 2009 the diversity and ecology of macrofungi is very scarce. In this context, the aim of this study Available online 21 July 2009 was to assess the macrofungal diversity associated with chestnut trees over 4 y. Carpo- Corresponding editor: Jacob phore surveys were conducted in a non-tilled C. sativa orchard located in Braganc¸a, Heilmann-Clausen Portugal, from Sep. 2002 to Dec. 2005. A total of 2677 carpophores belonging to 73 species across 16 families and 23 genera were recorded. Of the total number of macrofungal Keywords: species listed, 82 % were ectomycorrhizal (EM) species. The genera with the greatest Castanea sativa Mill species richness were Russula, Inocybe and Lactarius, which accounted for 38.4 % of all Fruiting phenology species collected. The most abundant species were Laccaria laccata, Hebeloma crustuliniforme Macrofungal occurrence and Inocybe geophylla, which produced around 35 % of all carpophores. The cumulative Macrofungal species diversity number of species over the four successive years revealed that 80.5 % of macrofungal species that potentially exist in the study area were surveyed. Species richness and carpophore abundance fluctuated across years, which could have been related to weather conditions, especially to rainfall. Fructification occurred in two distinct seasons a year, autumn and spring, the first one being the most important in terms of number of species and carpophores. These data could be an important contribution toward the development of sustainable management practices for chestnut agro-ecosystem conservation. ª 2009 Elsevier Ltd and The British Mycological Society. All rights reserved. Introduction Forest that produces high-quality timber is scarce and repre- sents less than 10 % of the total Portuguese chestnut area Portugal has the largest area of chestnut trees (Castanea sativa) (Anonymous 2007). Although chestnut is cultivated all over in the European Union (Anonymous 2006). The widespread Portugal, it is in the coldest areas in the north (The Tra´s-os- range of chestnut trees in this country is mainly related to the Montes region) that it is most important. In 2006, approxi- cultivated varieties in grafted orchards for fruit production. mately 85 % (25 644 ha) of the 30 097 ha of Portuguese chestnut * Corresponding author. Tel.: þ351 273303332; fax: þ351 273325405. E-mail address: [email protected] (P. Baptista). 1754-5048/$ – see front matter ª 2009 Elsevier Ltd and The British Mycological Society. All rights reserved. doi:10.1016/j.funeco.2009.06.002 10 P. Baptista et al. tree area was in the Tra´s-os-Montes region (Anonymous 2007). identified at the species level (Richard et al. 2004). In addition, The European chestnut tree, as a nut and timber producer, fruiting patterns, which allow for a comparison of current and plays an important role in the economy of the Tra´s-os-Montes historic carpophore data, constitute a valuable tool for region. Chestnut wood is one of the preferred choices in management and conservation strategies (Molina et al. 2001; making high quality furniture. The nuts constitute the most Richard et al. 2004). Carpophore surveys can also provide important export product of the Portuguese fruit sector insight into the characteristics of fungi and may explain their (Anonymous 2007). Additionally, over the last decade another habitat segregation (Matsuda & Hijii 1998). important income associated with these trees has emerged – The present study aims to provide information on the the collection and commercialization of wild edible mush- macrofungal community (EM and non-EM fungi) associated rooms growing in chestnut stands. Despite the poor knowledge with sweet chestnut tree in the Tra´s-os-Montes region of their biodiversity, ecology or sustainable management in (Northeast Portugal). A systematic survey was done over four those regions, mushroom harvesting is increasing, mainly consecutive years, from 2002 to 2005, in a chestnut orchard due to their economic importance to local populations. and the diversity (species richness and abundance), frequency Considering the species most frequently commercialized in of occurrence of macrofungal species and their fruiting the region (Amanita caesarea, Boletus edulis, B. aereus, Can- phenology were studied. The changes that occurred over time tharellus cibarius, Hydnum rufescens and Calocybe gambosa), in the macrofungal community was analyzed and related with small-scale studies indicated that the average total income climatic conditions (temperature and rainfall). can reach 134 V haÀ1 yÀ1 (Baptista et al. 2007). C. sativa establishes ectomycorrhizal (EM) associations with anumberoffungi(Harley & Harley 1987). Positive effects for the Methods chestnut plant were verified after mycorrhization with the EM fungi Pisolithus tinctorius (Martins 1997; Martins et al. 1997), Study area Laccaria laccata, Hebeloma crustuliniforme, H. sinapizans and Paxillus involutus (Branzanti et al. 1999). These associations The study was conducted in a 100þ-year-old non-tilled C. promote increased availability of mineral nutrients, growth and sativa orchard (about 1.5 ha of surface), located in Oleiros – productivity of chestnut plants, and exert a protective effect Braganc¸a (NE Portugal) (415101500N, 64902000W, 915 m a.s.l.) in against root pathogens (Martins 1997, 2004; Martins et al. 1997; the Natural Park of Montesinho (Fig 1). The orchard encom- Branzanti et al. 1999). Several cultivation practices have been passed a range of shrubs frequently associated with chestnut linked to the recent decline of chestnut tree, for example, soil trees, dominated by Genista sp. and Ulex sp. The only anthro- tillage contributes to the appearance of diseases such as pogenic disturbance during the research period was due to chestnut ink disease, caused by Phytophthora spp., and chestnut chestnut picking each Nov. For facilitating this process, the blight (Cypthonectria parasitica)(Martins et al. 2007). Since several current practice performed by locals is to remove soil debris EM fungi seem to exert a protective effect against root patho- with forks. The prevailing climate of the area is sub-conti- gens (Branzanti et al. 1999; Martins 2004), knowledge of the EM nental with long cold winters and short, hot and dry summers. fungal diversity associated with chestnut trees at a local scale The average annual rainfall ranges from 1000 to 1200 mm, will provide important information for management decisions about 90 % occurring between Oct. and Apr. The annual mean in the ecosystem. In Portugal, and specifically in the Tra´s-os- air temperature was 10–14 C, with temperatures ranging Montes region, lack of information on the diversity, abundance from 0 C (mean Jan. minima) to 28 C (mean Jul. maxima) and fruiting pattern of EM fungi associated with this ecosystem, (Agroconsultores & Coba 1991). The predominant soils are hinders development of new management practices. chromic dystric cambisols (according to FAO-Unesco-Isric Despite the symbiotic association between chestnut roots 1988) derived from migmatitic and gneissic parent materials, and some soil fungi having been previously described, and cover gentle to very gentle slopes (Agroconsultores & knowledge about diversity of EM fungi, their ecology, or Coba 1991). At a depth of 20 cm, the soil had a pH value of 5.3 sustainable management in chestnut stands is scarce, only and an organic matter content of 3.3 %. Total nitrogen (N) was short-term monitoring having been performed. To our 0.1 % while phosphorus (P2O5) and potassium (K2O) contents knowledge, there have been only two long-term studies in were 8 ppm and 320 ppm, respectively. chestnut coppices, comprising a period of 18-y in Greece During the surveyed period, meteorological data were (Diamandis & Perlerou 2001) and 4-y in central-southern collected at a weather station 5 km from the studied area. Tuscany (Italy) (Lagana` et al. 2002a). Another study was per- Cumulative rainfall and average daily temperatures (mean, formed during only one fruiting season in Romania (Chira & maximum and minimum) from 3, 10, 20 or 30 d before the Chira 2003). The identification of fungi in these studies was sampling date were determined. entirely based on their sexual reproductive structures, visible to the naked eye above ground. Surveys of EM fungal carpo- Fungal survey phores does not adequately reflect the below ground EM fungal diversity because some species lack carpophores or The study was conducted in five permanent non-contiguous have a sporulating strategy